The other day Lon introduced me to a fantastic site called http://www.gog.com/ (Good Old Games).
You can buy older games that might not work on today's PCs, they're cheap and DRM free! Plus after downloading you don't have to be connected to the net when playing them and you sometimes get extra stuff with them such as manuals, soundtracks and piccys.
This is fab for anyone like me who doesn't have Steam for whatever reason and I've found some real gems on here like: Baldur's Gate 1 & 2, Simon The Sorcerer 1 & 2, Myst 1 & 2 and Dark Fall 1 & 2
I definately reccomend checking it out!